public class

Vector

extends AbstractList<E>
implements Serializable Cloneable List<E> RandomAccess

java.lang.Object
↳	java.util.AbstractCollection<E>
	↳	java.util.AbstractList<E>
		↳	java.util.Vector<E>

Known Direct Subclasses

Stack<E>

Class Overview

Vector is a variable size contiguous indexable array of Objects. The size of the Vector is the number of Objects it contains. The capacity of the Vector is the number of Objects it can hold.

Objects may be inserted at any position up to the size of the Vector, increasing the size of the Vector. Objects at any position in the Vector may be removed, shrinking the size of the Vector. Objects at any position in the Vector may be replaced, which does not affect the Vector size.

The capacity of a Vector may be specified when the Vector is created. If the capacity of the Vector is exceeded, the capacity is increased, doubling by default.

Summary

Fields
protected int	capacityIncrement	How many elements should be added to the vector when it is detected that it needs to grow to accommodate extra entries.
protected int	elementCount	The number of elements or the size of the vector.
protected Object[]	elementData	The elements of the vector.

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Inherited Fields

From class java.util.AbstractList

Public Constructors
	Vector() Constructs a new Vector using the default capacity.
	Vector(int capacity) Constructs a new Vector using the specified capacity.
	Vector(int capacity, int capacityIncrement) Constructs a new Vector using the specified capacity and capacity increment.
	Vector(Collection<? extends E> collection) Constructs a new instance of `Vector` containing the elements in `collection`.

Public Methods
void	add(int location, E object) Adds the specified object into this Vector at the specified location.
boolean	add(E object) Adds the specified object at the end of this Vector.
synchronized boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified Collection at the specified location in this Vector.
synchronized boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified Collection to the end of this Vector.
synchronized void	addElement(E object) Adds the specified object at the end of this Vector.
synchronized int	capacity() Returns the number of elements this Vector can hold without growing.
void	clear() Removes all elements from this Vector, leaving it empty.
synchronized Object	clone() Returns a new Vector with the same elements, size, capacity and capacity increment as this Vector.
boolean	contains(Object object) Searches this Vector for the specified object.
synchronized boolean	containsAll(Collection<?> collection) Searches this Vector for all objects in the specified Collection.
synchronized void	copyInto(Object[] elements) Attempts to copy elements contained by this `Vector` into the corresponding elements of the supplied `Object` array.
synchronized E	elementAt(int location) Returns the element at the specified location in this Vector.
Enumeration<E>	elements() Returns an Enumeration on the elements of this Vector.
synchronized void	ensureCapacity(int minimumCapacity) Ensures that this Vector can hold the specified number of elements without growing.
synchronized boolean	equals(Object object) Compares the specified object to this Vector and answer if they are equal.
synchronized E	firstElement() Returns the first element in this Vector.
synchronized E	get(int location) Returns the element at the specified location in this Vector.
synchronized int	hashCode() Returns an integer hash code for the receiver.
int	indexOf(Object object) Searches in this Vector for the index of the specified object.
synchronized int	indexOf(Object object, int location) Searches in this Vector for the index of the specified object.
synchronized void	insertElementAt(E object, int location) Inserts the specified object into this Vector at the specified location.
synchronized boolean	isEmpty() Returns if this Vector has no elements, a size of zero.
synchronized E	lastElement() Returns the last element in this Vector.
synchronized int	lastIndexOf(Object object, int location) Searches in this Vector for the index of the specified object.
synchronized int	lastIndexOf(Object object) Searches in this Vector for the index of the specified object.
synchronized E	remove(int location) Removes the object at the specified location from this List.
boolean	remove(Object object) Removes the first occurrence, starting at the beginning and moving towards the end, of the specified object from this Vector.
synchronized boolean	removeAll(Collection<?> collection) Removes all occurrences in this Vector of each object in the specified Collection.
synchronized void	removeAllElements() Removes all elements from this Vector, leaving the size zero and the capacity unchanged.
synchronized boolean	removeElement(Object object) Removes the first occurrence, starting at the beginning and moving towards the end, of the specified object from this Vector.
synchronized void	removeElementAt(int location) Removes the element found at index position `location` from this `Vector` and decrements the size accordingly.
synchronized boolean	retainAll(Collection<?> collection) Removes all objects from this Vector that are not contained in the specified Collection.
synchronized E	set(int location, E object) Replaces the element at the specified location in this Vector with the specified object.
synchronized void	setElementAt(E object, int location) Replaces the element at the specified location in this Vector with the specified object.
synchronized void	setSize(int length) Sets the size of this Vector to the specified size.
synchronized int	size() Returns the number of elements in this Vector.
synchronized List<E>	subList(int start, int end) Returns a List of the specified portion of this Vector from the start index to one less than the end index.
synchronized <T> T[]	toArray(T[] contents) Returns an array containing all elements contained in this Vector.
synchronized Object[]	toArray() Returns a new array containing all elements contained in this Vector.
synchronized String	toString() Returns the string representation of this Vector.
synchronized void	trimToSize() Sets the capacity of this Vector to be the same as the size.

Protected Methods
void	removeRange(int start, int end) Removes the objects in the specified range from the start to the, but not including, end index.

[Expand]

Inherited Methods

From class java.util.AbstractList

void	add(int location, E object) Inserts the specified object into this List at the specified location.
boolean	add(E object) Adds the specified object at the end of this List.
boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified Collection at the specified location in this List.
void	clear() Removes all elements from this List, leaving it empty.
boolean	equals(Object object) Compares the specified object to this List and answer if they are equal.
abstract E	get(int location) Returns the element at the specified location in this List.
int	hashCode() Returns an integer hash code for the receiver.
int	indexOf(Object object) Searches this List for the specified object and returns the index of the first occurrence.
Iterator<E>	iterator() Returns an Iterator on the elements of this List.
int	lastIndexOf(Object object) Searches this List for the specified object and returns the index of the last occurrence.
ListIterator<E>	listIterator() Returns a ListIterator on the elements of this List.
ListIterator<E>	listIterator(int location) Returns a ListIterator on the elements of this List.
E	remove(int location) Removes the object at the specified location from this List.
void	removeRange(int start, int end) Removes the objects in the specified range from the start to the, but not including, end index.
E	set(int location, E object) Replaces the element at the specified location in this List with the specified object.
List<E>	subList(int start, int end) Returns a part of consecutive elements of this list as a view.

From class java.util.AbstractCollection

boolean	add(E object) If the specified element is not contained within this collection, and addition of this element succeeds, then true will be returned.
boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified Collection to this Collection.
void	clear() Removes all the elements in this collection.
boolean	contains(Object object) Searches this Collection for the specified object.
boolean	containsAll(Collection<?> collection) Searches this Collection for all objects in the specified Collection.
boolean	isEmpty() Returns true if the collection has no element, otherwise false.
abstract Iterator<E>	iterator() Returns an Iterator on the elements of this Collection.
boolean	remove(Object object) Removes the first occurrence of the specified object from this Collection.
boolean	removeAll(Collection<?> collection) Removes all occurrences in this Collection of each object in the specified Collection.
boolean	retainAll(Collection<?> collection) Removes all objects from this Collection that are not contained in the specified Collection.
abstract int	size() Returns the number of elements in this Collection.
<T> T[]	toArray(T[] contents) Returns an array containing all elements contained in this Collection.
Object[]	toArray() Returns a new array containing all elements contained in this Collection.
String	toString() Returns the string representation of this Collection.

From class java.lang.Object

Object	clone() Returns a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
boolean	equals(Object o) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
void	finalize() Called by the virtual machine when there are no longer any (non-weak) references to the receiver.
final Class<? extends Object>	getClass() Returns the unique instance of java.lang.Class which represents the class of the receiver.
int	hashCode() Returns an integer hash code for the receiver.
final void	notify() Causes one thread which is `wait` ing on the receiver to be made ready to run.
final void	notifyAll() Causes all threads which are `wait` ing on the receiver to be made ready to run.
String	toString() Returns a string containing a concise, human-readable description of the receiver.
final void	wait(long time, int frac) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait(long time) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait() Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by `notify` or `notifyAll`).

From interface java.lang.Iterable

From interface java.util.Collection

abstract boolean	add(E object) Attempts to add `object` to the contents of this `Collection`.
abstract boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `collection` to the contents of this collection.
abstract void	clear() Removes all elements from this Collection, leaving it empty.
abstract boolean	contains(Object object) Searches this Collection for the specified object.
abstract boolean	containsAll(Collection<?> collection) Searches this Collection for all objects in the specified Collection.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns if this Collection has no elements, a size of zero.
abstract Iterator<E>	iterator() Returns an instance of Iterator that may be used to access the objects contained by this collection.
abstract boolean	remove(Object object) Removes the first occurrence of the specified object from this Collection.
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this Collection of each object in the specified Collection.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this Collection that are not also found in the contents of `collection`.
abstract int	size() Returns a count of how many objects are contained by this collection.
abstract <T> T[]	toArray(T[] array) Returns an array containing all elements contained in this Collection.
abstract Object[]	toArray() Returns a new array containing all elements contained in this Collection.

From interface java.util.List

abstract void	add(int location, E object) Inserts the specified object into this Vector at the specified location.
abstract boolean	add(E object) Adds the specified object at the end of this List.
abstract boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified Collection at the specified location in this List.
abstract boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified Collection to the end of this List.
abstract void	clear() Removes all elements from this List, leaving it empty.
abstract boolean	contains(Object object) Searches this List for the specified object.
abstract boolean	containsAll(Collection<?> collection) Searches this List for all objects in the specified Collection.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract E	get(int location) Returns the element at the specified location in this List.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract int	indexOf(Object object) Searches this List for the specified object and returns the index of the first occurrence.
abstract boolean	isEmpty() Returns if this List has no elements, a size of zero.
abstract Iterator<E>	iterator() Returns an Iterator on the elements of this List.
abstract int	lastIndexOf(Object object) Searches this List for the specified object and returns the index of the last occurrence.
abstract ListIterator<E>	listIterator() Returns a ListIterator on the elements of this List.
abstract ListIterator<E>	listIterator(int location) Returns a ListIterator on the elements of this List.
abstract E	remove(int location) Removes the object at the specified location from this List.
abstract boolean	remove(Object object) Removes the first occurrence of the specified object from this List.
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this List of each object in the specified Collection.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this List that are not contained in the specified Collection.
abstract E	set(int location, E object) Replaces the element at the specified location in this List with the specified object.
abstract int	size() Returns the number of elements in this List.
abstract List<E>	subList(int start, int end) Returns a List of the specified portion of this List from the start index to one less than the end index.
abstract <T> T[]	toArray(T[] array) Returns an array containing all elements contained in this List.
abstract Object[]	toArray() Returns an array containing all elements contained in this List.

Fields

protected int capacityIncrement

How many elements should be added to the vector when it is detected that it needs to grow to accommodate extra entries.

protected int elementCount

The number of elements or the size of the vector.

protected Object[] elementData

The elements of the vector.

Public Constructors

public Vector ()

Constructs a new Vector using the default capacity.

public Vector (int capacity)

Constructs a new Vector using the specified capacity.

Parameters

capacity	the initial capacity of the new vector

public Vector (int capacity, int capacityIncrement)

Constructs a new Vector using the specified capacity and capacity increment.

Parameters

capacity	the initial capacity of the new Vector
capacityIncrement	the amount to increase the capacity when this Vector is full

public Vector (Collection<? extends E> collection)

Constructs a new instance of Vector containing the elements in collection. The order of the elements in the new Vector is dependent on the iteration order of the seed collection.

Parameters

collection	the collection of elements to add

Public Methods

public void add (int location, E object)

Adds the specified object into this Vector at the specified location. The object is inserted before any previous element at the specified location. If the location is equal to the size of this Vector, the object is added at the end.

Parameters

location	the index at which to insert the element
object	the object to insert in this Vector

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| > size()`

public boolean add (E object)

Adds the specified object at the end of this Vector.

Parameters

object	the object to add to the Vector

Returns

true

public synchronized boolean addAll (int location, Collection<? extends E> collection)

Inserts the objects in the specified Collection at the specified location in this Vector. The objects are inserted in the order in which they are returned from the Collection iterator.

Parameters

location	the location to insert the objects
collection	the Collection of objects

Returns

true if this Vector is modified, false otherwise

Throws

ArrayIndexOutOfBoundsException	when `location < 0` or `location > size()`

public synchronized boolean addAll (Collection<? extends E> collection)

Adds the objects in the specified Collection to the end of this Vector.

Parameters

collection	the Collection of objects

Returns

true if this Vector is modified, false otherwise

public synchronized void addElement (E object)

Adds the specified object at the end of this Vector.

Parameters

object	the object to add to the Vector

public synchronized int capacity ()

Returns the number of elements this Vector can hold without growing.

Returns

the capacity of this Vector

public void clear ()

Removes all elements from this Vector, leaving it empty.

public synchronized Object clone ()

Returns a new Vector with the same elements, size, capacity and capacity increment as this Vector.

Returns

a shallow copy of this Vector

public boolean contains (Object object)

Searches this Vector for the specified object.

Parameters

object	the object to look for in this Vector

Returns

true if object is an element of this Vector, false otherwise

public synchronized boolean containsAll (Collection<?> collection)

Searches this Vector for all objects in the specified Collection.

Parameters

collection	the Collection of objects

Returns

true if all objects in the specified Collection are elements of this Vector, false otherwise

public synchronized void copyInto (Object[] elements)

Attempts to copy elements contained by this Vector into the corresponding elements of the supplied Object array.

Parameters

elements	the `Object` array into which the elements of this Vector are copied

public synchronized E elementAt (int location)

Returns the element at the specified location in this Vector.

Parameters

location	the index of the element to return in this Vector

Returns

the element at the specified location

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| >= size()`

public Enumeration<E> elements ()

Returns an Enumeration on the elements of this Vector. The results of the Enumeration may be affected if the contents of this Vector are modified.

Returns

an Enumeration of the elements of this Vector

public synchronized void ensureCapacity (int minimumCapacity)

Ensures that this Vector can hold the specified number of elements without growing.

Parameters

minimumCapacity	the minimum number of elements that this vector will hold before growing

public synchronized boolean equals (Object object)

Compares the specified object to this Vector and answer if they are equal. The object must be a List which contains the same objects in the same order.

Parameters

object	the object to compare with this object

Returns

true if the specified object is equal to this Vector, false otherwise

public synchronized E firstElement ()

Returns the first element in this Vector.

Returns

the element at the first position

Throws

NoSuchElementException	when this vector is empty

public synchronized E get (int location)

Returns the element at the specified location in this Vector.

Parameters

location	the index of the element to return in this Vector

Returns

the element at the specified location

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| >= size()`

public synchronized int hashCode ()

Returns an integer hash code for the receiver. Objects which are equal answer the same value for this method.

Returns

the receiver's hash

public int indexOf (Object object)

Searches in this Vector for the index of the specified object. The search for the object starts at the beginning and moves towards the end of this Vector.

Parameters

object	the object to find in this Vector

Returns

the index in this Vector of the specified element, -1 if the element isn't found

public synchronized int indexOf (Object object, int location)

Searches in this Vector for the index of the specified object. The search for the object starts at the specified location and moves towards the end of this Vector.

Parameters

object	the object to find in this Vector
location	the index at which to start searching

Returns

the index in this Vector of the specified element, -1 if the element isn't found

Throws

ArrayIndexOutOfBoundsException	when `location < 0`

public synchronized void insertElementAt (E object, int location)

Inserts the specified object into this Vector at the specified location. This object is inserted before any previous element at the specified location. If the location is equal to the size of this Vector, the object is added at the end.

Parameters

object	the object to insert in this Vector
location	the index at which to insert the element

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| > size()`

public synchronized boolean isEmpty ()

Returns if this Vector has no elements, a size of zero.

Returns

true if this Vector has no elements, false otherwise

public synchronized E lastElement ()

Returns the last element in this Vector.

Returns

the element at the last position

Throws

NoSuchElementException	when this vector is empty

public synchronized int lastIndexOf (Object object, int location)

Searches in this Vector for the index of the specified object. The search for the object starts at the specified location and moves towards the start of this Vector.

Parameters

object	the object to find in this Vector
location	the index at which to start searching

Returns

the index in this Vector of the specified element, -1 if the element isn't found

Throws

ArrayIndexOutOfBoundsException	when `location >= size()`

public synchronized int lastIndexOf (Object object)

Searches in this Vector for the index of the specified object. The search for the object starts at the end and moves towards the start of this Vector.

Parameters

object	the object to find in this Vector

Returns

the index in this Vector of the specified element, -1 if the element isn't found

public synchronized E remove (int location)

Removes the object at the specified location from this List.

Parameters

location	the index of the object to remove

Returns

the removed object

public boolean remove (Object object)

Removes the first occurrence, starting at the beginning and moving towards the end, of the specified object from this Vector.

Parameters

object	the object to remove from this Vector

Returns

true if the specified object was found, false otherwise

public synchronized boolean removeAll (Collection<?> collection)

Removes all occurrences in this Vector of each object in the specified Collection.

Parameters

collection	the Collection of objects to remove

Returns

true if this Vector is modified, false otherwise

public synchronized void removeAllElements ()

Removes all elements from this Vector, leaving the size zero and the capacity unchanged.

public synchronized boolean removeElement (Object object)

Removes the first occurrence, starting at the beginning and moving towards the end, of the specified object from this Vector.

Parameters

object	the object to remove from this Vector

Returns

true if the specified object was found, false otherwise

public synchronized void removeElementAt (int location)

Removes the element found at index position location from this Vector and decrements the size accordingly.

Parameters

location	the index of the element to remove

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| >= size()`

public synchronized boolean retainAll (Collection<?> collection)

Removes all objects from this Vector that are not contained in the specified Collection.

Parameters

collection	the Collection of objects to retain

Returns

true if this Vector is modified, false otherwise

public synchronized E set (int location, E object)

Replaces the element at the specified location in this Vector with the specified object.

Parameters

location	the index at which to put the specified object
object	the object to add to this Vector

Returns

the previous element at the location

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| >= size()`

public synchronized void setElementAt (E object, int location)

Replaces the element at the specified location in this Vector with the specified object.

Parameters

object	the object to add to this Vector
location	the index at which to put the specified object

Throws

ArrayIndexOutOfBoundsException	when `location < 0 \|\| >= size()`

public synchronized void setSize (int length)

Sets the size of this Vector to the specified size. If there are more than length elements in this Vector, the elements at end are lost. If there are less than length elements in the Vector, the additional elements contain null.

Parameters

length	the new size of this Vector

public synchronized int size ()

Returns the number of elements in this Vector.

Returns

the number of elements in this Vector

public synchronized List<E> subList (int start, int end)

Returns a List of the specified portion of this Vector from the start index to one less than the end index. The returned List is backed by this Vector so changes to one are reflected by the other.

Parameters

start	the index at which to start the sublist
end	the index one past the end of the sublist

Returns

a List of a portion of this Vector

Throws

IndexOutOfBoundsException	when `start < 0 or end > size()`
IllegalArgumentException	when `start > end`

public synchronized T[] toArray (T[] contents)

Returns an array containing all elements contained in this Vector. If the specified array is large enough to hold the elements, the specified array is used, otherwise an array of the same type is created. If the specified array is used and is larger than this Vector, the array element following the collection elements is set to null.

Parameters

contents	the array

Returns

an array of the elements from this Vector

Throws

ArrayStoreException	when the type of an element in this Vector cannot be stored in the type of the specified array

public synchronized Object[] toArray ()

Returns a new array containing all elements contained in this Vector.

Returns

an array of the elements from this Vector

public synchronized String toString ()

Returns the string representation of this Vector.

Returns

the string representation of this Vector

public synchronized void trimToSize ()

Sets the capacity of this Vector to be the same as the size.

Protected Methods

protected void removeRange (int start, int end)

Removes the objects in the specified range from the start to the, but not including, end index.

Parameters

start	the index at which to start removing
end	the index one past the end of the range to remove

Throws

IndexOutOfBoundsException	when `start < 0, start > end` or `end > size()`

Jan	FEB	Mar
	18
2008	2009	2010

Interfaces

Classes

Enums

Exceptions

Vector

Class Overview

See Also

Summary

Fields

protected int capacityIncrement

protected int elementCount

protected Object[] elementData

Public Constructors

public Vector ()

public Vector (int capacity)

Parameters

public Vector (int capacity, int capacityIncrement)

Parameters

public Vector (Collection<? extends E> collection)

Parameters

Public Methods

public void add (int location, E object)

Parameters

Throws

See Also

public boolean add (E object)

Parameters

Returns

public synchronized boolean addAll (int location, Collection<? extends E> collection)

Parameters

Returns

Throws

public synchronized boolean addAll (Collection<? extends E> collection)

Parameters

Returns

public synchronized void addElement (E object)

Parameters

public synchronized int capacity ()

Returns

See Also

public void clear ()

See Also

public synchronized Object clone ()

Returns

See Also

public boolean contains (Object object)

Parameters

Returns

See Also

public synchronized boolean containsAll (Collection<?> collection)

Parameters

Returns

public synchronized void copyInto (Object[] elements)

Parameters

See Also

public synchronized E elementAt (int location)

Parameters

Returns

Throws

See Also

public Enumeration<E> elements ()

Returns

See Also

public synchronized void ensureCapacity (int minimumCapacity)

Parameters

See Also

public synchronized boolean equals (Object object)

Parameters

Returns

See Also

public synchronized E firstElement ()

Returns

Throws

See Also

public synchronized E get (int location)

Parameters

Returns

Throws

See Also

public synchronized int hashCode ()